Many moving apparatus, such as aircraft, spacecraft, ships, missiles, rockets, satellites, vehicles, or other types of moving apparatus require guidance systems. Gyroscopes are sometimes used for this purpose. One prior art gyroscope disclosed by U.S. Pat. No. 7,352,471 utilizes a system embedded interferometric fiber optic gyroscope in which a coil, support optics, and electronic components are mounted on a frame which is then mounted directly to the system instrument mount. However, this prior art gyroscope only utilizes one coil size which does not allow for the flexibility of serving different functions. For instance, if the coil is small, it may be suitable for flight stability functions but not for gyrocompassing. Conversely, if the coil is large, it may be suitable for gyrocompassing. It may also be used for flight stability or another function but that would be an inefficient use of an expensive coil and make the system unnecessarily large. Another prior art gyroscope disclosed by U.S. Pat. No. 6,198,094 utilizes two nested coils of the same size and a third coil of the same size which is disposed in non-nested arrangement at the bottom of the two nested coils. However, this prior art gyroscope again only utilizes one coil size which does not allow for the flexibility of serving different functions, nor does it allow for instruments, such as accelerometers, to be disposed between the nested coils. Additionally, this prior art gyroscope is packaged in a strap-down cylinder and does not allow for the gyroscope to be packaged in a minimized, volume-saving sphere.
An interferometric fiber optic gyroscope and method of its manufacture is needed to decrease one or more problems associated with one or more of the existing fiber optic gyroscopes. In particular, a small, lightweight, accurate, interferometric fiber optic gyroscope is desired which is adapted to serve varying functions while being able to hold varying types of instruments.